Mechanical indexer for multi-station process module

ABSTRACT

A process module for a substrate processing tool includes a plurality of processing stations each configured to perform a process on a substrate and a mechanical indexer arranged within the process module. The mechanical indexer includes a plurality of end effectors including at least a first end effector, a second end effector, and a third end effector. Each of the plurality of end effectors extends in a radial direction from a central axis of the mechanical indexer and is configured to rotate about the central axis within the process module. The mechanical indexer is configured to position each of the plurality of end effectors at any one of the plurality of processing stations within the process module. The mechanical indexer is configured to position more than one of the plurality of end effectors at a same one of the plurality of processing stations at a same time.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure is a continuation of U.S. patent application Ser.No. 15/868,347, filed on Jan. 11, 2018, which claims the benefit of U.S.Provisional Application No. 62/449,325, filed on Jan. 23, 2017. Theentire disclosures of the applications referenced above are incorporatedherein by reference.

FIELD

The present disclosure relates to transfer of substrates within processmodules of substrate processing systems.

BACKGROUND

The background description provided here is for the purpose of generallypresenting the context of the disclosure. Work of the presently namedinventors, to the extent it is described in this background section, aswell as aspects of the description that may not otherwise qualify asprior art at the time of filing, are neither expressly nor impliedlyadmitted as prior art against the present disclosure.

A substrate processing system may be used to perform deposition, etchingand/or other treatment of substrates such as semiconductor wafers.During processing, a substrate is arranged on a substrate support in aprocessing chamber of the substrate processing system. Gas mixturesincluding one or more precursors are introduced into the processingchamber and plasma may be struck to activate chemical reactions. Thesubstrate processing system may include a plurality of substrateprocessing tools arranged within a fabrication room. Each of thesubstrate processing tools may include a plurality of process modules.

Referring now to FIG. 1, a top-down view of an example substrateprocessing tool 100 is shown. The substrate processing tool 100 includesa plurality of process modules 104. Each of the process modules 104 maybe configured to perform one or more respective processes on asubstrate. Substrates to be processed are loaded into the substrateprocessing tool 100 via ports of a load station of an equipment frontend module (EFEM) 108 and then transferred into one or more of theprocess modules 104. For example, substrates may be transferred from theEFEM 108 to a load lock 112 via one or more EFEM robots 116. A vacuumtransfer module (VTM) 120 includes one or more VTM robots 124 configuredto transfer the substrates into and out of the process modules 104. Forexample, a substrate may be loaded into each of the process modules 104in succession.

In one example, the process modules 104 correspond to quad stationprocess modules (QSMs). A QSM may include four processing stations 128within a single chamber (i.e., within a process chamber 132 of theprocess module 104). Substrates 136 are loaded into the process module104 via a load station 140. For example, substrates 136 are transferredbetween the VTM 120 and the load stations 140 via respective slots 144between the VTM 120 and the process modules 104. A mechanical indexer148 (i.e., an indexing mechanism) sequentially rotates the substrates136 between the processing stations 128. As shown, the mechanicalindexer 148 corresponds to a cross-shaped spindle. For example, thesubstrate 136 may be transferred from the VTM 120 to the processingstation 128 corresponding to the load station 140 (labelled “1”),rotated sequentially between the processing stations 140 labelled “2,”“3”, and “4,” and then returned to the load station 140 for removal fromthe process module 104. A system controller 152 may control variousoperations of the tool, including, but not limited to, operation of therobots 116 and 124, rotation of the indexers 148, etc.

SUMMARY

A mechanical indexer for a substrate processing tool includes first andsecond arms each having first and second end effectors. The first arm isconfigured to rotate on a first spindle to selectively position thefirst end effector of the first arm at a plurality of processingstations of the substrate processing tool and selectively position thesecond end effector of the first arm at the plurality of processingstations of the substrate processing tool. The second arm is configuredto rotate on a second spindle to selectively position the first endeffector of the second arm at the plurality of processing stations ofthe substrate processing tool and selectively position the second endeffector of the second arm at the plurality of processing stations ofthe substrate processing tool. At least one of the plurality ofprocessing stations corresponds to a load station of the substrateprocessing tool. The first arm is configured to rotate independently ofthe second arm such that the first end effector or the second endeffector of the first arm is positioned at the load station while thefirst end effector or the second end effector of the second arm ispositioned at the load station.

In other features, the first spindle and the second spindle are coaxial.Each of the first arm and the second arm is configured to be raised andlowered relative to the plurality of processing stations of thesubstrate processing tool. The second spindle is disposed within thefirst spindle.

In other features, the first arm and the second arm are rotatable into afirst configuration. In the first configuration, the first end effectorand the second end effector of the first arm are positioned at a firstprocessing station and a third processing station, respectively, of theplurality of processing stations and the first end effector and thesecond end effector of the second arm are positioned at a secondprocessing station and a fourth processing station, respectively, of theplurality of processing stations. The first arm and the second arm arerotatable into a second configuration. In the second configuration, thefirst end effector and the second end effector of the first arm arepositioned at the first processing station and the third processingstation, respectively, of the plurality of processing stations and thefirst end effector and the second end effector of the second arm arepositioned at the third processing station and the first processingstation, respectively, of the plurality of processing stations.

In other features, the first processing station corresponds to the loadstation of the substrate processing tool. The first processing stationand the third processing station are arranged at opposite corners of thesubstrate processing tool and the second processing station and thefourth processing station are arranged at opposite corners of thesubstrate processing tool.

In other features, the first arm and the second arm are rotatable into afirst configuration. In the first configuration, the first end effectorand the second end effector of the first arm are positioned at a firstprocessing station and a fourth processing station, respectively, of theplurality of processing stations and the first end effector and thesecond end effector of the second arm are positioned at a secondprocessing station and a third processing station, respectively, of theplurality of processing stations. The first arm and the second arm arerotatable into a second configuration. In the second configuration, thefirst end effector and the second end effector of the first arm arepositioned at the first processing station and the fourth processingstation, respectively, of the plurality of processing stations and thefirst end effector and the second end effector of the second arm arepositioned at the fourth processing station and the first processingstation, respectively, of the plurality of processing stations.

In other features, the first processing station and the fourthprocessing station are arranged on a first side of the substrateprocessing tool and the second processing station and the thirdprocessing station are arranged on a second side of the substrateprocessing tool opposite the first side. The first processing stationand the fourth processing station correspond to load stations of thesubstrate processing tool.

In other features, a substrate processing tool includes a vacuumtransfer module and a plurality of process modules coupled to the vacuumtransfer module. At least one of the plurality of process modulesincludes the mechanical indexer. The plurality of process modulesincludes first and second process modules coupled to a first side of thevacuum transfer module and third and fourth process modules coupled to asecond side of the vacuum transfer module.

In other features, an adapter plate is arranged between the first sideand the first and second process modules. The adapter plate includes aplanar side configured to interface with the first side of the vacuumtransfer module and an angled side configured to interface with thefirst and second process modules.

In other features, the first side and the second side of the vacuumtransfer module are chamfered. An adapter plate is arranged between thefirst side and the first and second process modules. The adapter plateincludes an angled side configured to interface with the first side ofthe vacuum transfer module and a planar side configured to interfacewith the first and second process modules.

Further areas of applicability of the present disclosure will becomeapparent from the detailed description, the claims and the drawings. Thedetailed description and specific examples are intended for purposes ofillustration only and are not intended to limit the scope of thedisclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an example substrate processing tool.

FIG. 2A shows a first example process module with a mechanical indexerin an X-shaped configuration.

FIG. 2B shows the first example process module with the mechanicalindexer in a second configuration.

FIG. 2C is a side view of the first example process module.

FIG. 2D is a side view of the mechanical indexer.

FIG. 3A shows a second example process module with a mechanical indexerin an X-shaped configuration.

FIG. 3B shows the second example process module with the mechanicalindexer in a second configuration.

FIG. 3C is a side view of the second example process module.

FIG. 3D shows the mechanical indexer in the X-shaped configuration.

FIG. 3E shows the mechanical indexer in the second configuration.

FIG. 4A shows a first example substrate processing tool.

FIG. 4B shows a second example substrate processing tool.

FIG. 4C shows an example transfer robot.

FIG. 4D shows an example adapter plate for a substrate processing tool.

FIG. 4E shows a third example substrate processing tool.

FIG. 5 shows steps of a first example method for operating a mechanicalindexer of a substrate processing tool.

FIG. 6 shows steps of a second example method for operating a mechanicalindexer of a substrate processing tool.

In the drawings, reference numbers may be reused to identify similarand/or identical elements.

DETAILED DESCRIPTION

Process modules in a substrate processing tool may be operated in amultiple station, sequential processing mode. For example, only aportion of the overall process may be performed on a substrate in eachof the process stations in the process module. As process times in eachof the stations decreases and/or the process module performs a greaternumber of processes on the substrate, delays associated with rotatingand transferring the substrate via a mechanical indexer become a greaterportion of a total time each substrate remains in the process module. Inone example, substrates are sequentially transferred to the processstation corresponding to the load station. The indexer is rotatedsubsequent to each transfer until a substrate is arranged on the indexerin each of the four process stations. Processing may then be performedon each of the substrates.

Substrate processing and transfer systems and methods according to theprinciples of the present disclosure implement a transfer module (e.g.,a vacuum transfer module, or VTM), process module, and mechanicalindexer configured to reduce substrate transfer times. For example, theVTM is configured to load two or more (e.g., four) substrates into theprocess module and to retrieve two or more substrates from the processmodule per transfer.

In one example, the mechanical indexer comprises two independentlyrotatable arms, each having first and second ends (e.g., end effectors).The indexer may be selectively arranged in a first, X-shapedconfiguration. In the X-shaped configuration, each of the ends may bealigned with a respective processing station in the process module. Forexample, first and second ends of a first arm may be aligned withdiagonally opposite processing stations 1 and 3 (or 2 and 4) while firstand second ends of a second arm may be aligned with diagonally oppositeprocessing stations 2 and 4 (or 1 and 3). In a second configuration, oneof the arms is raised and rotated such that the first arm and the secondarm are aligned. In the second configuration, the first and second endsof each of the arms are aligned with stations 1 and 3 or 2 and 4. Inother words, in the second configuration, respective ends of both armsmay be vertically stacked in any one of the processing stations. Inparticular, respective ends of both arms may be aligned with the loadstation.

Accordingly, in this example, two substrates may be transferred toand/or from the process module (e.g., using a VTM robot havingvertically stacked end effectors configured to transfer two substratesat a time). Both arms may be rotated such that opposite ends of each ofthe arms are aligned with the load station to transfer two additionalsubstrates to and/or from the process module. The mechanical indexer maythen be arranged into the first X-shaped configuration such that each ofthe four substrates is aligned with a different processing station.

In another example, the process module may include two load stations.For example, the load stations may correspond to processing stationsadjacent to the VTM. In this example, the mechanical indexer includesfirst and second V-shaped arms. The indexer may be arranged in a first,X-shaped configuration. In the X-shaped configuration, first and secondends of the first V-shaped arm may be aligned with processing stations 1and 4 (or processing stations 2 and 1, 3 and 2, or 4 and 3) while firstand second ends of the second V-shaped arm may be aligned withprocessing stations 2 and 3 (or processing stations 3 and 4, 4 and 1, or1 and 2). In a second configuration, one of the arms is raised androtated such that the first arm and the second arm are aligned. In thesecond configuration, the first and second ends of each of the arms arealigned with, for example, stations 1 and 4, which may correspond to theload stations. In other words, in the second configuration, respectiveends of both arms may be vertically stacked in the load stations.

Accordingly, in this example, four substrates may be transferred toand/or from the process module (e.g., using two VTM robots each havingvertically stacked end effectors configured to transfer two substratesat a time). The mechanical indexer may then be arranged into the firstX-shaped configuration such that each of the four substrates is alignedwith a different processing station.

As described below in more detail, the substrate processing and transfersystems and methods according to the present disclosure may reduceenergy consumption, reduce overhead time associated with substrateprocessing, increase processing throughput, increase the number ofprocess modules per tool, etc. Although described with respect toprocess modules having four processing stations, the principles of thepresent disclosure may also be implemented in process modules havingother numbers of processing stations (e.g., two, three, five, six,seven, eight, etc.).

Referring now to FIGS. 2A, 2B, 2C, and 2D an example process module 200including a mechanical indexer 204 according to the principles of thepresent disclosure is shown. In this example, the mechanical indexer 204comprises two independently rotatable arms 208 and 212, each havingfirst and second ends (e.g., end effectors 216, 220, 224, and 228). Theindexer 204 is arranged in a first, X-shaped configuration in FIG. 2Aand a second configuration in FIG. 2B. In the X-shaped configuration,the end effectors 216 and 220 of the first arm 208 are positioned overprocessing stations 1 and 3, respectively, and the end effectors 224 and228 are positioned over processing stations 2 and 4, respectively. Theprocessing station 1 may correspond to a load station 232 accessible viaslot 236.

In the second configuration, the second arm 212 may be raised androtated such that the first arm 208 and the second arm 212 are aligned.For example, the first arm 208 may be coupled to a first spindle 240 andthe second arm 212 may be coupled to a second spindle 244 as shown inFIG. 2D. The second spindle 244 is enclosed within the first spindle 240and is configured to be selectively raised and lowered inside the firstspindle 240. Accordingly, raising the second spindle 244 raises thesecond arm 212 relative to the first arm 208, allowing the second arm212 to be rotated independently of the first arm 208. In this manner,the end effectors 216, 220, 224, and 228 and respective substrates 248may be positioned above/below one another in the load station 232 or anyone of the processing stations 1-4.

For example, the second arm 212 may be rotated such that the first arm208 and the second arm 212 are arranged in the second configurationshown in FIG. 2B. In the second configuration, the end effectors 216 and228 are each located in the load station 232. In other words, in thesecond configuration, the end effectors 216 and 228 are verticallystacked in the load station 232. Accordingly, the substrates 248arranged on the end effectors 216 and 228 may be retrieved from theprocess module 200 and/or new (i.e., unprocessed) substrates may beloaded onto the end effectors 216 and 228 via the slot 236.

In one example transfer sequence, each of the first arm 208 and thesecond arm 212 are raised to a first elevation to lift the substrates248 from the respective processing stations 1-4. For example, endeffectors 216, 220, 224, and 228 may be positioned at processingstations 1, 2, 3, and 4, respectively. The second arm 212 may be furtherraised to a second elevation above the first elevation. Accordingly, thesecond arm 212 may be rotated (e.g., approximately 90 degrees in aclockwise direction as shown in FIG. 2B) such that the end effector 228is positioned at processing station 1 (i.e., the load station 332). AVTM robot external to the process module 200 may then retrieve thesubstrates 248 arranged on each of the end effectors 216 and 228. Insome examples, the VTM robot swaps the processed substrates 248 withunprocessed substrates.

Subsequent to unloading the substrates 248 and/or loading unprocessedsubstrates onto the end effectors 216 and 228, the entire indexer 204(i.e., both the first arm 208 and the second arm 212) may be rotatedapproximately 180 degrees while maintaining the respective first andsecond elevations of the first arm 208 and the second arm 212.Accordingly, the indexer 204 is rotated such that end effectors 220 and224 are positioned at the loading station 232. The VTM robot may thenretrieve the processed substrates 248 from the end effectors 220 and 224and/or load unprocessed substrates onto the end effectors 220 and 224.The second arm 212 may then be rotated (e.g., approximately 90 degreesin the clockwise direction) relative to the arm 208 to position the endeffectors 224 and 228 at processing stations 2 and 4, respectively whilethe end effectors 216 and 220 remain at processing stations 3 and 1,respectively. Each of the first arm 208 and the second arm 212 may thenbe lowered to position the unprocessed substrates in the respectiveprocessing stations 1-4. Other example transfer sequences may beimplemented.

Referring now to FIGS. 3A, 3B, 3C, 3D, and 3E, another example processmodule 300 including a mechanical indexer 304 according to theprinciples of the present disclosure is shown. In this example, theprocess module 300 includes two load stations 308 and 312 andcorresponding slots 316 and 320. The indexer 304 includes first andsecond V-shaped arms 324 and 328 each having first and second ends(e.g., end effectors 332, 336, 340, and 344). The indexer 304 isarranged in a first, X-shaped configuration in FIGS. 3A and 3D and asecond configuration in FIGS. 3B and 3E. In the X-shaped configuration,the end effectors 332 and 336 are position over processing stations 1and 4, respectively, and the end effectors 340 and 344 are positionedover processing stations 2 and 3, respectively. The processing stations1 and 4 correspond to the load stations 308 and 320, respectively.

In the second configuration, the second arm 328 may be raised androtated such that the first arm 324 and the second arm 328 are aligned.For example, the first arm 324 and the second arm 328 may be coupled toindependently rotatable spindles 348 and 352 configured to operates in amanner analogous to the first and second spindles 240 and 244 asdescribed in FIG. 2D. Accordingly, the second arm 328 may be rotatedsuch that the first arm 324 and the second arm 328 are arranged in thesecond configuration shown in FIG. 3B. In the second configuration, theend effectors 332 and 344 are each located in the load station 308 andthe end effectors 336 and 340 are each located in the load station 312.For example, the end effectors 332 and 344 and corresponding substrates356 arranged thereon are vertically stacked in the load station 308.Conversely, the end effectors 336 and 340 and the correspondingsubstrates 356 arranged thereon are vertically stacked in the loadstation 312. Accordingly, the substrates 356 may be retrieved from theprocess module 300 and/or new (i.e., unprocessed) substrates may beloaded onto the end effectors 332, 344 and 336, 340 via respective slots316 and 320.

In one example transfer sequence, each of the first arm 324 and thesecond arm 328 are raised to a first elevation to lift the substrates356 from the respective processing stations 1-4. For example, endeffectors 332, 340, 344, and 336 may be positioned at processingstations 1, 2, 3, and 4, respectively. The second arm 328 may be furtherraised to a second elevation above the first elevation. Accordingly, thesecond arm 328 may be rotated (e.g., approximately 180 degrees as shownin FIG. 3B) such that the end effectors 344 and 340 are positioned atprocessing stations 1 and 2, respectively (i.e., the load stations 308and 312). A VTM robot external to the process module 300 may thenretrieve the substrates 356 arranged on each of the end effectors 332,340, 344, and 336. In some examples, the VTM robot swaps the processedsubstrates 356 with unprocessed substrates.

Subsequent to unloading the substrates 356 and/or loading unprocessedsubstrates onto the end effectors 332, 340, 344, and 336, the second arm328 is rotated approximately 180 degrees to return the indexer 304 tothe X-shaped configuration while maintaining the respective first andsecond elevations of the first arm 324 and the second arm 328.Accordingly, the end effectors 332, 340, 344, and 336 are positioned atthe processing stations 1, 2, 3, and 4, respectively. The first arm 324and the second arm 328 may then be lowered onto the respectiveprocessing stations 1-4. Other example transfer sequences may beimplemented.

Referring now to FIGS. 4A, 4B, and 4C, top-down views of examplesubstrate processing tools 400 and 404 having example transfer robots408-1, 408-2, and 408-3, referred to collectively as transfer robots408, are shown. The processing tools 400 and 404 are shown withoutmechanical indexers for example purposes. For example, respectiveprocess modules 412 of each of the tools 400 and 404 may include eitherof the mechanical indexer 204 and the mechanical indexer 304 asdescribed above.

A vacuum transfer module (VTM) 416 and an equipment front end module(EFEM) 420 may each include one of the transfer robots 408. The transferrobots 408-1 and 408-2 may have the same or different configurations.For example only, the transfer robot 408-1 includes a single arm havingtwo vertically stacked end effectors. Conversely, the transfer robot408-2 is shown having two arms, each having two vertically stacked endeffectors as shown in FIG. 4C. The robot 408 of the VTM 416 selectivelytransfers substrates to and from a load lock 424 and between the processmodules 412. The robot 408-3 of the EFEM 420 transfers substrates intoand out of the EFEM 420 and to and from the load lock 424. For exampleonly, the robot 408-3 may have two arms each having a single endeffector or two vertically stacked end effectors.

The tool 400 is configured to interface with, for example, four of theprocess modules 412 each having a single load station accessible via arespective slot 428. Conversely, the tool 404 is configured to interfacewith three of the process modules 412 each having two load stationsaccessible via respective slots 432 and 436. As shown, sides 440 of theVTM 416 may be angled (e.g., chamfered) to facilitate coupling withdifferent arrangements (e.g., different amounts, spacing, etc.) of theprocess modules 412.

For example, as shown in FIG. 4A, the VTM is coupled to two of theprocess modules 412 per side 440. Conversely, the shape of the VTM 416also allows for the connection of process modules 412 having two loadstations. For example, an adapter plate 444 having the two slots 432 and436 may be provided to accommodate a single process module 412 havingtwo load stations as shown in FIG. 4B. As shown, the adapter plate 444has a first, angled side configured to interface with the angled side440 of the VTM 416 and a second, non-angled (i.e., straight or flat)side configured to interface with the process module 412. Accordingly,the VTM 416 provides the flexibility of allowing connection of a greaternumber of process modules 412 having a single load station (i.e., toincrease the number of process stations per unit area of the tool 400)while also allowing the flexibility of using process modules 412 havingonly one load station as shown in FIG. 4A or two load stations as shownin FIG. 4B. In other examples, sides of the VTM 416 may be non-angled(i.e., straight or flat). In these examples, the tool 400 may include anadapter plate 446, as shown in FIG. 4D, configured to interface with twoprocess modules 412 each having a single load station. In other words,instead of converting the angled side 440 of the VTM 416 to a non-angledside, the adapter plate 446 converts a non-angled side of the VTM 416 toan angled side.

The robot 408-2 of the VTM 416 includes two arms 448 and 452 eachincluding two vertically stacked end effectors 456 for a total of fourof the end effectors 456. Accordingly, each of the arms 448 and 452 isconfigured to simultaneously transfer two substrates to and/or from arespective one of the process modules 412, the load lock 424, etc. Inthe example shown in FIG. 4A, the robot 408-1 may retrieve twosubstrates from the process module 412 and load two substrates into theprocess module 412 in a given transfer. Conversely, the robot 408-2 mayretrieve four substrates from the process module 412 and load foursubstrates into the process module 412 in a given transfer.

A system controller 460 may control various operations of the substrateprocessing tools 400 and 404, including, but not limited to, operationof the robots 408, rotation of the respective indexers of the processmodules 412 (e.g., corresponding to the indexers 204 and 304 of FIGS. 2and 3), etc.

In another example shown in FIG. 4E, a substrate processing tool 464includes transfer robots 468-1 and 468-2, referred to collectively astransfer robots 468. The processing tool 464 is shown without mechanicalindexers for example purposes. For example, respective process modules472 of the tool 464 may include either of the mechanical indexer 204 andthe mechanical indexer 304 as described above.

A VTM 476 and an EFEM 480 may each include one of the transfer robots468. The transfer robots 468-1 and 468-2 may have the same or differentconfigurations. For example only, the transfer robot 468-1 is shownhaving two arms, each having two vertically stacked end effectors asshown in FIG. 4C. The robot 468-1 of the VTM 476 selectively transferssubstrates to and from the EFEM 480 and between the process modules 472.The robot 468-2 of the EFEM 480 transfers substrates into and out of theEFEM 480. For example only, the robot 468-2 may have two arms eachhaving a single end effector or two vertically stacked end effectors.

The tool 464 is configured to interface with, for example, four of theprocess modules 472 each having a single load station accessible via arespective slot 484. In this example, sides 488 of the VTM 476 are notangled (i.e., the sides 488 are substantially straight or planar). Inthis manner, two of the process modules 472, each having a single loadstation, may be coupled to each of the sides 488 of the VTM 476.Accordingly, the EFEM 480 may be arranged at least partially between twoof the process modules 472 to reduce a footprint of the tool 464.

Referring now to FIG. 5, a first example method 500 for operating amechanical indexer of a substrate processing tool begins at 504 (e.g.,the mechanical indexer 204 as shown in FIGS. 2A, 2B, 2C, and 2D). Forexample only, operation of the mechanical indexer may be controlled by acontroller, such as the system controller 460. At 508, the mechanicalindexer is arranged in a first, X-shaped configuration where first andsecond ends of a first arm are positioned at first and third processingstations and first and second ends of a second arm are positioned atsecond and fourth processing stations (e.g., as shown in FIG. 2A). Eachof the ends of the first and second arms may be positioned to retrieve arespective processed substrate. At 512, the first arm and the second armare raised on respective spindles to lift the substrates from theprocessing stations. At 516, the second arm is rotated (e.g., 90 degreesin a clockwise direction as shown in FIG. 2B) such that the second endof the second arm is positioned at the first processing station, whichmay correspond to a load station. At 520, a robot retrieves theprocessed substrates from the first end of the first arm and the secondend of the second arm positioned at the first processing station.

At 524, the robot transfers unprocessed substrates to the first end ofthe first arm and the second end of the second arm positioned at thefirst processing station. At 528, the first arm and the second arm arerotated (e.g., 180 degrees) such that the second end of the first armand the first end of the second arm are each positioned at the firstprocessing station. At 532, the robot retrieves the processed substratesfrom the first end of the first arm and the second end of the secondarm. At 536, the robot transfers unprocessed substrates to the secondend of the first arm and the first end of the second arm positioned atthe first processing station. At 540, the second arm is rotated (e.g.,90 degrees in a clockwise direction) such that the first and second endsof the second arm are positioned at the second and fourth processingstations (i.e., the mechanical indexer is returned to the first,X-shaped configuration). At 544, the first and second arms are loweredto position the unprocessed substrates onto the respective processingstations. The method 500 ends at 548.

Referring now to FIG. 6, a second example method 600 for operating amechanical indexer of a substrate processing tool begins at 604 (e.g.,the mechanical indexer 304 as shown in FIGS. 3A, 3B, 3C, 3D, and 3E).For example only, operation of the mechanical indexer may be controlledby a controller, such as the system controller 460. At 608, themechanical indexer is arranged in a first, X-shaped configuration wherefirst and second ends of a first arm are positioned at first and fourthprocessing stations and first and second ends of a second arm arepositioned at second and third processing stations (e.g., as shown inFIG. 3A). Each of the ends of the first and second arms may bepositioned to retrieve a respective processed substrate. At 612, thefirst arm and the second arm are raised on respective spindles to liftthe substrates from the processing stations. At 616, the second arm isrotated (e.g., 180 degrees in a clockwise direction as shown in FIG. 3B)such that the first and second ends of the second arm are positioned atthe fourth and first processing stations, respectively, which may eachcorrespond to a load station. At 620, one or more robots retrieve theprocessed substrates from the first and second ends of the first arm andthe first and second ends of the second arm positioned at the first andfourth processing stations.

At 624, the robot transfers unprocessed substrates to the first andsecond ends of the first arm and the first and second ends of the secondarm positioned at the first and fourth processing stations. At 628, thesecond arm is rotated (e.g., 180 degrees) such that the first and secondends of the second arm are positioned at the second and third processingstations (i.e., the mechanical indexer is returned to the first,X-shaped configuration). At 632, the first and second arms are loweredto position the unprocessed substrates onto the respective processingstations. The method 600 ends at 636.

The foregoing description is merely illustrative in nature and is in noway intended to limit the disclosure, its application, or uses. Thebroad teachings of the disclosure can be implemented in a variety offorms. Therefore, while this disclosure includes particular examples,the true scope of the disclosure should not be so limited since othermodifications will become apparent upon a study of the drawings, thespecification, and the following claims. It should be understood thatone or more steps within a method may be executed in different order (orconcurrently) without altering the principles of the present disclosure.Further, although each of the embodiments is described above as havingcertain features, any one or more of those features described withrespect to any embodiment of the disclosure can be implemented in and/orcombined with features of any of the other embodiments, even if thatcombination is not explicitly described. In other words, the describedembodiments are not mutually exclusive, and permutations of one or moreembodiments with one another remain within the scope of this disclosure.

Spatial and functional relationships between elements (for example,between modules, circuit elements, semiconductor layers, etc.) aredescribed using various terms, including “connected,” “engaged,”“coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and“disposed.” Unless explicitly described as being “direct,” when arelationship between first and second elements is described in the abovedisclosure, that relationship can be a direct relationship where noother intervening elements are present between the first and secondelements, but can also be an indirect relationship where one or moreintervening elements are present (either spatially or functionally)between the first and second elements. As used herein, the phrase atleast one of A, B, and C should be construed to mean a logical (A OR BOR C), using a non-exclusive logical OR, and should not be construed tomean “at least one of A, at least one of B, and at least one of C.”

In some implementations, a controller is part of a system, which may bepart of the above-described examples. Such systems can comprisesemiconductor processing equipment, including a processing tool ortools, chamber or chambers, a platform or platforms for processing,and/or specific processing components (a wafer pedestal, a gas flowsystem, etc.). These systems may be integrated with electronics forcontrolling their operation before, during, and after processing of asemiconductor wafer or substrate. The electronics may be referred to asthe “controller,” which may control various components or subparts ofthe system or systems. The controller, depending on the processingrequirements and/or the type of system, may be programmed to control anyof the processes disclosed herein, including the delivery of processinggases, temperature settings (e.g., heating and/or cooling), pressuresettings, vacuum settings, power settings, radio frequency (RF)generator settings, RF matching circuit settings, frequency settings,flow rate settings, fluid delivery settings, positional and operationsettings, wafer transfers into and out of a tool and other transfertools and/or load locks connected to or interfaced with a specificsystem.

Broadly speaking, the controller may be defined as electronics havingvarious integrated circuits, logic, memory, and/or software that receiveinstructions, issue instructions, control operation, enable cleaningoperations, enable endpoint measurements, and the like. The integratedcircuits may include chips in the form of firmware that store programinstructions, digital signal processors (DSPs), chips defined asapplication specific integrated circuits (ASICs), and/or one or moremicroprocessors, or microcontrollers that execute program instructions(e.g., software). Program instructions may be instructions communicatedto the controller in the form of various individual settings (or programfiles), defining operational parameters for carrying out a particularprocess on or for a semiconductor wafer or to a system. The operationalparameters may, in some embodiments, be part of a recipe defined byprocess engineers to accomplish one or more processing steps during thefabrication of one or more layers, materials, metals, oxides, silicon,silicon dioxide, surfaces, circuits, and/or dies of a wafer.

The controller, in some implementations, may be a part of or coupled toa computer that is integrated with the system, coupled to the system,otherwise networked to the system, or a combination thereof. Forexample, the controller may be in the “cloud” or all or a part of a fabhost computer system, which can allow for remote access of the waferprocessing. The computer may enable remote access to the system tomonitor current progress of fabrication operations, examine a history ofpast fabrication operations, examine trends or performance metrics froma plurality of fabrication operations, to change parameters of currentprocessing, to set processing steps to follow a current processing, orto start a new process. In some examples, a remote computer (e.g. aserver) can provide process recipes to a system over a network, whichmay include a local network or the Internet. The remote computer mayinclude a user interface that enables entry or programming of parametersand/or settings, which are then communicated to the system from theremote computer. In some examples, the controller receives instructionsin the form of data, which specify parameters for each of the processingsteps to be performed during one or more operations. It should beunderstood that the parameters may be specific to the type of process tobe performed and the type of tool that the controller is configured tointerface with or control. Thus as described above, the controller maybe distributed, such as by comprising one or more discrete controllersthat are networked together and working towards a common purpose, suchas the processes and controls described herein. An example of adistributed controller for such purposes would be one or more integratedcircuits on a chamber in communication with one or more integratedcircuits located remotely (such as at the platform level or as part of aremote computer) that combine to control a process on the chamber.

Without limitation, example systems may include a plasma etch chamber ormodule, a deposition chamber or module, a spin-rinse chamber or module,a metal plating chamber or module, a clean chamber or module, a beveledge etch chamber or module, a physical vapor deposition (PVD) chamberor module, a chemical vapor deposition (CVD) chamber or module, anatomic layer deposition (ALD) chamber or module, an atomic layer etch(ALE) chamber or module, an ion implantation chamber or module, a trackchamber or module, and any other semiconductor processing systems thatmay be associated or used in the fabrication and/or manufacturing ofsemiconductor wafers.

As noted above, depending on the process step or steps to be performedby the tool, the controller might communicate with one or more of othertool circuits or modules, other tool components, cluster tools, othertool interfaces, adjacent tools, neighboring tools, tools locatedthroughout a factory, a main computer, another controller, or tools usedin material transport that bring containers of wafers to and from toollocations and/or load ports in a semiconductor manufacturing factory.

What is claimed is:
 1. A process module for a substrate processing tool,the process module comprising: a plurality of processing stations eachconfigured to perform a process on a substrate; and a mechanical indexerarranged within the process module, wherein the mechanical indexercomprises a plurality of end effectors including at least a first endeffector, a second end effector, and a third end effector, wherein eachof the plurality of end effectors extends in a radial direction from acentral axis of the mechanical indexer and is configured to rotate aboutthe central axis within the process module, the mechanical indexer isconfigured to position each of the plurality of end effectors at any oneof the plurality of processing stations within the process module, andthe mechanical indexer is configured to position more than one of theplurality of end effectors at a same one of the plurality of processingstations at a same time.
 2. The process module of claim 1, wherein themechanical indexer is configured to position each of the plurality ofend effectors at a loading station of the process module at a same time.3. The process module of claim 1, wherein at least one of the pluralityof processing stations is a load station of the process module.
 4. Theprocess module of claim 3, further comprising a first slot aligned withthe load station, wherein the first slot provides access to the loadstation from a vacuum transfer module external to the process module. 5.The process module of claim 4, wherein the mechanical indexer isconfigured to receive at least two substrates through the first slot ata same time.
 6. The process module of claim 3, wherein two of theplurality of processing stations are load stations of the processmodule, the process module further comprising: a first slot stationaligned with a first one of the load stations, wherein the first slotprovides access to the load station from a vacuum transfer moduleexternal to the process module; and a second slot aligned with a secondone of the load stations, wherein the second slot provides access to theload station from the vacuum transfer module
 7. The process module ofclaim 6, wherein the mechanical indexer is configured to receive, at asame time, two substrates through the first slot and two substratethrough the second slot.
 8. The process module of claim 1, wherein: themechanical indexer comprises a first arm including the first endeffector and the second end effector; and the mechanical indexercomprises a second arm including the third end effector and a fourth endeffector, wherein the mechanical indexer is configured to rotate thefirst arm and the second arm into an X-shaped configuration such thateach of the first end effector, the second end effector, the third endeffector, and the fourth end effector are positioned at different onesof the plurality of processing stations, and rotate the first arm andthe second arm such that at least two the first end effector, the secondend effector, the third end effector, and the fourth end effector arevertically stacked at a same one of the plurality of processingstations.
 9. The process module of claim 8, wherein the same one of theplurality of processing stations is a load station aligned with a slotthat provides access to the load station from a vacuum transfer moduleexternal to the process module.
 10. The process module of claim 8,wherein: each of the first arm and the second arm is V-shaped; two ofthe plurality of processing stations are load stations aligned withrespective slots that provide access to the load stations from a vacuumtransfer module external to the process module; and the mechanicalindexer is configured to rotate the first arm and the second arm suchthat, at a same time, (i) each of the first end effector and the thirdend effector are positioned at a first one of the load stations and (ii)each of the second end effector and the fourth end effector arepositioned at a second one of the load stations.
 11. The process moduleof claim 1, wherein a quantity of the plurality of end effectors and aquantity of the plurality of processing stations in the process moduleis the same.
 12. The process module of claim 1, wherein the plurality ofend effectors consists of the first end effector, the second endeffector, the third end effector, and a fourth end effector and theplurality of processing stations consists of four processing stations.